SHT-30 Weatherproof Probe
A solution for coldchain monitoring using the SHT-30 weatherproof temperature and humidity probe wired to an ESP32 gateway board.
The sensor
A research-grade temperature and humidity probe in a weatherproof mesh tube on a 1 meter cable, wired straight to the gateway board. Measures ±0.5 °C and ±2 % RH, powered by the board itself: no batteries in the cold.
| Measures | Temperature and relative humidity, both from the one probe |
|---|---|
| Temperature accuracy | ±0.5 °C typical |
| Humidity accuracy | ±2 % RH typical |
| Interface | I2C (address 0x44), pullups built into the cable; four wires: power, ground, clock, data |
| Cable | 1 meter, weatherproof mesh-protected tip (breathes air, not for submersion) |
| Power | 3 to 5 V DC from the board; no batteries |
What you’ll need
1 × SHT-30 weatherproof probe
The probe lives in the cold space; its 1 meter cable carries power and readings to the board outside.
1 × An ESP32 board
Reads the probe over I2C and pushes each reading to the endpoint you own.
1 × IP65 sealed project box
Keeps the board dry when it mounts in a washdown room, a barn, or outside.
1 × USB power supply and data cable
Powers the board around the clock; the probe is powered by the board.
How it works
The probe reads temperature and humidity inside the cold space. Its cable carries power in and readings out to the gateway board, which pushes each reading to the endpoint you choose: your webhook, your MQTT broker, or the Test Bench.
No radio between sensor and record, no batteries in the cold, no subscription.
Questions folks ask
When is a wired probe better than a wireless thermometer?
When you want humidity as well as temperature from the cold space, when radio cannot reach, or when you do not want batteries inside the cold at all. The wire carries power in and readings out, and nothing ever needs a battery change.
Does the SHT-30 read humidity inside a cooler?
Yes. It reads temperature to about ±0.5 °C and relative humidity to about ±2 %, both from the one probe, which matters in produce storage where humidity decides shelf life.
How long can the cable be?
The probe ships with 1 meter. I2C is a short-run bus: keep the probe cable short and put the board close to the cold space, or step up to an RS-485/SDI-12 instrument for long runs.